Field of the Invention
This invention relates to a memory protection circuit and a liquid crystal display device including the same.
Discussion of the Related Art
A liquid crystal display is one of the flat panel displays which are most widely used, and includes two substrates having pixel electrodes, a common electrode, and the like, and a liquid crystal layer interposed between the two substrates. The liquid crystal display displays an image by determining orientations of liquid crystal molecules of the liquid crystal layer through an electric field generated by a voltage applied to the electrodes, and controlling polarization of an incident light. The liquid crystal display is advantageous to display moving images and has a high contrast ratio. Thus, the liquid crystal display can be substituted for cathode ray tube displays, and has been variously used as a display device of mobile terminals (notebook monitor, etc.), computer monitors, televisions, and the like.
The liquid crystal display includes an electrically erasable programmable read only memory (EEPROM) which reads model information, such as resolution and timing, from a system even during a system booting process, to transmit the model information to a liquid crystal driving circuit unit. The EEPROM is a readable and writable memory. However, in the process of manufacturing a liquid crystal display, the write protection function of the EEPROM is enabled and thus the write function is disabled in a state of a liquid crystal module (LCM) that typically includes a liquid crystal panel, driving circuits, and a case. In other words, since the write protection function of the EEPROM is not enabled before the liquid crystal module is fabricated, EEPROM data may be often damaged and transformed by external electric shocks or the like.